package com.ltt.utils;

/**
 * @author ‘李天泰’
 * @version 1.0
 * @description: TODO
 * @date 2023/5/11 9:23
 */

import com.alibaba.fastjson.JSONObject;

import javax.servlet.http.HttpServletRequest;
import java.io.IOException;
import java.nio.charset.StandardCharsets;

/**
 *  转换reqeest工具类
 **/
public class GetRequestJsonUtils {

    public static JSONObject getRequestJsonObject(HttpServletRequest request) throws IOException {
        String json = getRequestJsonString(request);
        return JSONObject.parseObject(json);
    }

    /***
     * 获取 request 中 json 字符串的内容
     *
     * @param request
     * @return : <code>byte[]</code>
     * @throws IOException
     */
    public static String getRequestJsonString(HttpServletRequest request)
            throws IOException {
        String submitMehtod = request.getMethod();
        // GET
        if (submitMehtod.equals("GET")) {
            return new String(request.getQueryString().getBytes(StandardCharsets.ISO_8859_1), StandardCharsets.UTF_8).replaceAll("%22", "\"");
            // POST
        } else {
            return getRequestPostStr(request);
        }
    }

    /* @param request
     * @return
     * @throws IOException
     */
    public static byte[] getRequestPostBytes(HttpServletRequest request)
            throws IOException {
        int contentLength = request.getContentLength();
        if (contentLength < 0) {
            return null;
        }
        byte[] buffer = new byte[contentLength];
        for (int i = 0; i < contentLength; ) {
            int readlen = request.getInputStream().read(buffer, i,
                    contentLength - i);
            if (readlen == -1) {
                break;
            }
            i += readlen;
        }
        return buffer;
    }

    /**
     * 描述:获取 post 请求内容
     * <pre>
     * 举例
     * </pre>
     *
     * @param request
     * @return
     * @throws IOException
     */
    public static String getRequestPostStr(HttpServletRequest request) {
        try {
            byte[] buffer = getRequestPostBytes(request);
            String charEncoding = request.getCharacterEncoding();
            if (charEncoding == null) {
                charEncoding = "UTF-8";
            }
            return new String(buffer, charEncoding);
        } catch (Exception e) {
            e.printStackTrace();
        }
        return null;
    }

}
